The development of a routine screening analysis for myoglobin in serum, myoglobinemia, is the goal of this research. Myoglobinemia is currently pictured as the first serum indicator of myocardial infarction and is possibly of more diagnostic utility than the isoenzyme of creatine phosphokinase or lactate dehydrogenase analyses. The latter two serum indicators do not appear in serum for at least 24 hours after the occurrence of a myocardial infarction. The research involves the use of surface modified gold minigrid electrode which was recently developed in the author's laboratory. Gold minigrid electrodes have been electrochemically modified with 1,1'-dimethyl-4-,4'-dipyridinium dichloride (methyl viologen) and they exhibit quasi-reversible rates of direct reduction or oxidation with myoglobin. In the absence of the surface modification gold electrodes do not reduce or oxidize myoglobin appreciably. The surface modified electrode will be incorporated in an amperometric detector for myoglobinemia analysis after separation of myoglobin from other constituents of serum by high performance liquid chromatography. The use of the surface modified gold electrode in the amperometric detector should provide the sensitivity and the chromatography should provide the selectivity required for an analysis for myoglobinemia. The physical and chemical characterization of the surface modification using surface spectroscopic methods (ESCA, auger, SIMS) and electrochemical kinetic measurements.